Release: J98-34

NEW PROGRAM SMOOTHS X-38 TEST
OPERATIONS

A flexible, effective monitoring
and control program with wide applications for the X-38
project has been developed by the Automation, Robotics and Simulation
Division of the Engineering Directorate at the Johnson Space Center.

The program, called Portable
Diagnostic Terminal software, uses National Instrument Co.ís Labview
language to enable an IBM Thinkpad to monitor systems of the prototype
X-38 before and after flight and provide limited pre- and post-flight
command capability.

Frank Delgado of the Engineering
Directorate headed up the software project, which resulted in the development
of the application in less than a year.

"The approach we used minimized
the number of engineers needed to create the software," Delgado said.
"We used an object-oriented approach to develop a common set of displays
that could be used to create other monitoring applications."

The software is used on the
ground to monitor the X-38ís health and status before flight tests.
It can turn systems on and off.

During flight tests, while
the X-38 is attached to the wing of a B-52, the terminal with the new
software is wired to the vehicle and is used to prepare it for free
flight. With it, the launch panel operator can declare the X-38 "ready
for flight," the last step before the pilotís decision to release the
craft.

The fully functional software
was delivered to the X-38 program in 1997. It has been used in six captive
carry tests, with the X-38 remaining attached to the B-52, and one free-flight
test.

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The application will be used
for the remaining flight tests of the current X-38 prototype. It also
will be used in flight testing of a subsequent X-38 prototype, which
will begin this fall.

"The application lets us look
into the vehicle," said Debbie Buscher, software lead of the of the
X-38 program. "Itís our one way of communicating with the vehicle and
determining whatís going on before release."

She said methods used by Delgado
and his team to develop the software resulted in a quick and rational
development process.

The X-38 concept could become
the first new spacecraft in two decades to orbit the Earth. The initial
goal of the project was to develop a crew return vehicle for the International
Space Station. The concept could be modified for other uses, including
perhaps a joint U.S. and international human spacecraft that could be
used in conjunction with any of several U.S. or international launchers.

Flight testing of the X-38,
developed in a project with a strong focus on economy and efficiency,
began last year.